I have ordered two brushless motors for hovercraft.
They are 12v, 18000 rpm.
How much amp. ESC should be used with it. Please give some link of brushless ESC if you know.

And also tell the use of ESC, What will happen if I dont use a ESC?

I Dont know much.....but know that brushless esc is must for brushless motors...... If u dont use Esc and directly connect the motor to battery it will burn up.... .:-(   

In order to select ESC you need to know the current rating of motor. Do u know the current rating...?
the Key to select ESC is.... current rating of ESC should be more than current rating of motor.

Quote from: mrhot111 on November 23, 2010, 07:51:49 PM
And also tell the use of ESC, What will happen if I dont use a ESC?

Search on this forum... if you are getting into this hobby, you really really need to spend some time learning at least the very basics, it will help you in every step of the way in your project

An ESC allows you to control the speed of the motor (both brushed and brushless).  Without ESC, you can make brushed motors run continuously at full power, but for brushless motors, the different sets of windings have to be fed power in cycles to keep the rotation going, which means that an ESC with appropriate timing is a must.

Thanks Anwar, I will read about it.
And about current rating, i will confirm and post soon tomorrow.

Insert Quote
I Dont know much.....but know that brushless esc is must for brushless motors...... If u dont use Esc and directly connect the motor to battery it will burn up.... .:-(   

So that means If I want to put brushless motors directly on model with a switch to operate without connecting it with reciever, then also I need a ESC. Am I right?

Quote from: mrhot111 on November 24, 2010, 11:21:55 PM
So that means If I want to put brushless motors directly on model with a switch to operate without connecting it with reciever, then also I need a ESC. Am I right?

Brushless motor has 3 wires and it's working is different from regular DC motors.
You can google for it...there are lot of links which explain how it works.
You will need ESC to run Brushless motor.

Since brushless motors operate with good amount of current.....connecting them to power source without speed controller can lead to frying of brushless motor.
So never connect brushless motor to battery without speed controller.

Brushless motor cannot be installed with an ESC if you don't have a receiver. How will you control the speed of the motor without a Tx/Rx? After all, the ESC controls the speed of the motor (RPM) and it is connected and controlled via the Rx which receives the signals from the Tx.

If you are planning to use Brushless motors, you need the full setup of Brushless ESC, Batteries, Rx (Therefore Tx), Servos for the Rudders.

If you just want to build a Hovercraft that can GO, use brushed motors and the toy car Tx/ Rx with a built in battery chamber on board the model. No ESC required here. This is where you can use the manual switches. One for lift - switch it on and the skirt inflates, switch the other one on and she starts to move forward. No Tx/Rx required here. Make sure that the rudder is fixed tight. This is the simplest design for a 'electrically operated model Hovercraft' but the movement can't be controlled.

This has reference to my conversation with Mr. Hot earlier this evening.

Seniors please correct me if I am wrong  here.

The 27mhz radio has two nonpropotional channels right. So why not use a switch to keep the skirt inflated (remains inflated untill turned off - switch is on the hovercraft). One channel to turn on/off the motor for movement. One channel connecte to another motor for rudder movement - the motor rotated cock-wise and anti-clockwise to move rudder either direction.

Else can differential power be used? Two fans/props(dunno what to call it) on the left and right trailing edge. Differential power to change direction.

Or can a fan be placed in the plane perpendicular to plane of fwd/aft movement for steering?

Ot onr motor for thrust and another to rotate the first motor to change direction of thrust.

Liked the first idea of rajathv8. Thanks.

Hi Guys
I wanted to order two Turnigy 20A Brushed ESC for my brother as he is making a tracked vehicle. I wanted to run those ESC on one Battery. So which battery can be used. The input voltage is 2s-3s.

come on Guys

you can use any 2s (7.4v) or 3s (11.1v) battery depending on your motor.

I wanted to use only one Lipo

Hi,
Your motor surely have a current rating or a wattage rating specified.
The rating is for full throttle.

If you have wattage rating,
Amps = wattage/(Max.Volts*.9) --- Taking 0.9 is efficiency as wattage is the Mech Power output.
Again,
If you got current,
Your Mech. Power output = Current * Max. Volt * 0.9   ---Taking 0.9 as efficiency.

Please note that the motors run actually on 3 phase AC motor principle and the ESC makes DC to 3 phase AC.

Now, again, The current rating of the ESC comes from the final stage pass transistor and so, the peak current capacity that it can handlewithout overheat is it's capacity.

Therefore, if you have require a 90 watt mech. output for stable flying, you have to keep  at least 180 watt of motor  and 180/(11.1*0.9) =18.1A i. e. 21/25A ESC (Next Higher value).

Battery should be capable to deliver 20A discharge, i. e. 20C 1000mAH 3S or 25C 800mAH 3S or 35C 600mAH 3S.

Here look, 1x20 = 20, 0.8x25 = 20, 35 x 0.6 = 21.

VED,

If you want to use 1S battery, then check the ESC for battery voltage support.
The ESC have generally serve two purpose.
1. Convert the Supply voltage to Motor required supply proportional to input.
2. Make +5 Volt supply for receiver control.

If you want to use 1S battery, check the ESC Data before purchase. Because, generally function 2 is done by series regulator and not by boosting battery supply.

Therefore, you have to use simple speed controller and have to use separate Receiver supply.

I am drawing Brushed speed controller Schematics. Rathikrishna is expert in that field and I am linking that page.

http://www.modelboatmayhem.co.uk/forum/index.php?topic=27882.0

Thanks

Hey KALYANPRODHAN 
Thanks for so much information.Acctualy i needed those ESC for a vehicke and not for a plane.

Hi Guys, 
Today I was testing my boat. When I connected the battery to the ESC no beep was emitted.But the light on receiver was on. Please help me to sort the mistake out.

Edit:sorry i posted in the wrong thread.

Beep comes from the motor. connect it.

Also after I connect it to the motor, the beep does not come.

Sorry I did not read the above posts, looks like its a brushed ESC. Not sure how they work  In this case, dont know if the sound comes or not.

Hey Guys,
Can any body tell me how to start Hobbyking SS25-30A ESC ?

How to start? When its connected to the battery it powers up without any human intervention

I hope you have soldered appropriate connectors and shrink wrapped them.
Also while connecting to Reciever be very carefull about the polarity.